Gas distribution arrangement for rotary reactor

Abstract

A port assembly for controlling the delivery of gases into the horizontal rotating reactor such as kiln gasifier is disclosed for introducing reactant gases. The port assembly comprises a cylindrical conduit is divided into noncommunicating four or more sections extending through the entire length of the kiln and supported by the stationary end plates of the rotating kiln gasifier. Each section of the conduit communicates with external supply of the reactant gases and each supply of reactant gases is independently controlled in terms of the composition and quantity. Each section of the port assembly communicates with the interior of the kiln gasifier through the plurality of nozzles are confined in the lower part of the conduit. The number and the size of the nozzles in individual section of the conduit is based on the desired flow of gases and available pressure for the supply of the reactant gases.

Description

PRIOR RELATED APPLICATION DATA[0001]This application is a continuation of U.S. application Ser. No. 12 / 463,848, filed May 11, 2009, which claims priority to Indian Patent Application No. 1157 / CHE / 2008, filed May 12, 2008, the entire content of which is incorporated herein by reference in its entirety.BACKGROUND OF INVENTION[0002]1. Field of Invention[0003]This invention relates to reactors such as rotary kilns for the gasification of mixed size of solid carbonaceous materials such as biomass and solid wastes in a tumbling state and particularly to the gas distribution port for introducing gases such as air, oxygen, and steam to the interior of the rotary kiln wherein this gas distributor assures gas solid mixing inside the reactor to promote gas solid reaction.[0004]2. General Background and the State of the Art[0005]In the last two decades or so, interest in biomass gasification has picked up as means of producing energy from renewable resources to supplement the foreign imports as...

AI Technical Summary

Benefits of technology

The present invention provides a port assembly for delivering independently controlled flow of reactant gases to specific sections of a rotary kiln. The port assembly allows for the reaction of the gases with the solids present inside the kiln, providing better contact and allowing for more efficient reaction. The port assembly includes a main conduit with multiple sections for introducing different gases and allows for individual control over the gas composition and amount supplied to each section. This promotes greater reactivity with the solids and reduces the formation of byproducts. The gasification reactions in the gasifier require less oxygen than complete combustion, resulting in a smaller gasifier and easier cleaning. The gas produced is a high-quality fuel suitable for various applications.

Problems solved by technology

Even though this art provides means of introducing air into the kiln either below the material charge of the bed or when the ports are above the bed, its operation, control, and maintenance is cumbersome.

If aforesaid apparatus is operated to process mixed size materials containing particles having smaller diameter than the port, these smaller particles may enter the ports and the associated piping causing the clogging of the ports and thereby restricting the flow of air into the reactor.

This sort of impairment also increases the necessity of maintenance and hence increases the downtime of the reactor.

While this improvement act to prevent particulate material from entering the associated port pipe, some of the very smallest particulate material will eventually elude this screening mechanism and pass into the piping and eventually cause a restriction for the air flow into the reactor.

This method, however is complex and tedious.

In this study it is implied that significant amount of carbon is left in the solid residue and unless used as fuel for indirect heating of the kiln shell, the process efficiency for converting biomass into fuel gas is greatly diminished.

This port is however based on uniform disbursement of air and steam from around each section of the port which may result largely in undesirable gas to gas reaction rather than intended gas to solid reaction.

This particular distributor has limited ability to cause intense mixing between the gas and solids in the reactor which is a prerequisite for causing optimum conversion of solid biomass and other solid carbonaceous fuels into gaseous fuel.

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